Single vs double oil ring pistons --make that double compression rings

[wobble]

What are the advantages/disadvantages between these two options?

[SUB454]

What are the advantages/disadvantages between these two options?

Me don't know :'( I think Preddy runs a Venom piston(single). Where's Kenny?

[wobble]

Preddy said it has less resistance so it gives more power and revs quicker, but you have to replace the rings, actually ring....that just sounds funny , more often. This makes sense, and I'm sure he's right. I was hoping for some further discussion on this. It seems a single ring set up is not that common. I was wonder why that is the case. 

[RaptorRandy]

This is a CP single top ring piston. They offer all the advantages you stated. Yes they do require ring replacement more often....that's about the only down side, but if you get a total seal type ring then you will have a little longer longevity and have maximum ring seal with a much reduced leak down percentage IMHO. 

[wobble]

Let's see if I understand this correctly. So the single ring setup gives you more power. However, it wears quickly, thus increasing the leakdown. Therefore this power will begin to drop off at a much faster rate than running dual rings? 

It seems that most of us frequent these forums in the constant search for more power. If the single ring setup gives that, then why don't more of us use it? There are alot of us here who tear down their engines every winter anway. 

[Krandall]

RR, What's a "total seal type"  is it just a solid ring vs a split ring?

[RaptorRandy]

Let's see if I understand this correctly. So the single ring setup gives you more power. However, it wears quickly, thus increasing the leakdown. Therefore this power will begin to drop off at a much faster rate than running dual rings? 

It seems that most of us frequent these forums in the constant search for more power. If the single ring setup gives that, then why don't more of us use it? There are alot of us here who tear down their engines every winter anway. 

Not so much as drop off at a much faster rate if you replace the rings (top and oil) before their wore out.
That's why I leak down test my engine after multi day dune trips.....if the leak down gets excessive then you know it's time to replace the rings.  The single Top ring pistons are considered to be a "Race" piston 

[RaptorRandy]

RR, What's a "total seal type"  is it just a solid ring vs a split ring?

It's still split you just have a rail like on an oil ring that you stagger so there is no longer a gap for compression to leak by.

This is a pic of a standard total seal second ring.

[preddy08]

I will be contacting Venom soon to see about running a single "total seal type" top ring fior his pistons.


If anyone is willing to bum me a leak down tester I will share my complete and un-bias finding. I would love to find that out too. I dont have time to get one togeather. I'm working 60 hour work weeks, planning a wedding, and trying to find time to ride and get in shape for up and coming races.

[RaptorRandy]

Here's a link to a real reasonably priced leak down tester that you can order online. I like the dual gauge type myself .

http://store.summitracing.com/partdetail.asp?autofilter=1&part=SUM%2D900010&N=700+4294925139+4294925138+4294854847+4294854754+400304+115&autoview=sku

[preddy08]

If I get a wild butt hair this winter I will get that ordered up. It wont be for another month or two. Our last race is early novenber.


Does anyone see why one could'nt run a single total seal ring setup?

[preddy08]

I'll tell ya now, I have'nt felt any noticeable power lose or ANY oil consumption..........what so ever.

[wobble]

I think I'll be picking one of them up. Looks like another valuable tool to have.

[RaptorRandy]

If I get a wild butt hair this winter I will get that ordered up. It wont be for another month or two. Our last race is early novenber.


Does anyone see why one could'nt run a single total seal ring setup?

No reason not to that I know of 

The total seal gapless top ring is just the natural evolution of the gapless second ring. By moving the gapless ring to the #1 ring groove it effectively seals the cylinder closer to the combustion chamber. This not only increases the cylinder seal on the compression and power stokes, but also improves the ring seal on the intake stroke resulting in better cylinder filling on a normally aspirated engine. The increased amount of force generated by the combustion process in turn delivers a greater amount of energy to the crankshaft.  Either gapless top ring or 2nd ring offers superior cylinder sealing. This is from the total seal tech page as there's no way I could explain it any better in my own words.


Randy

[wobble]

As someone just pointed on the "other" forum, I meant to say double compression rings, not double oil rings. I hadn't yet finished drinking my pot of coffee when I posted that.